| dc.description.abstract | The Theory oj Plastic Mechanism Control (TPMC), based on the
application oj the kinematic theorem oj the plastic collapse, has been
developed in the nineties with rejerence to moment-resisting jrames
(MRFs) and progressively extended to several steel structural typologies,
commonly adopted as seismic-resistant structural system. The aim oj this
PhD thesis is the study oj a simple procedure to design moment resisting
concrete jrames. This methodology allows to dejine structures having a
smart behaviour when subjected to seismic excitation. Infact, the structure
develops the maximum number oj dissipative zones by means oj a
particular collapse mechanism: the global one. In particular, the outcome
oj the theory is the evaluation oj the sum oj the plastic moments oj the
columns required, at each storey, to prevent undesiredjailure modes such
as sojt-storey mechanism. In the proposed method the second-order
effects, due to vertical loads, can play an important rale in the seismic
design oj reinforced concrete jrames; they can be taken into account by
mean the mechanism equilibrium curve oj the considered collapse
mechanism. To complete the study, is important to consider a comparison
between the design oj a reinjorced concrete jrame according code rules
i.e. adopting the hierarchy criteria and the same frame designed by the
Theory oj Plastic Mechanism Contro!. The TPMC is a more sophisticated
design procedure because it works in jull compliance with codes
recommendations considering that it respects the hierarchy criteria. These
last, in jact, are jundamental to avo id dangerous collapse mechanisms
such as "sojt-storey" mechanism but they are not sufficient to guarantee
the exploitation oj the maximum dissipation capacity oj the frame To validate the TPMC design procedure several practical applications
with reference to the design of a multi-storey frame are presented.
In addition, both push-over analyses and non.-linear dynamic analyses
have been made to investigate the actual collapse mechanism of the
designed structure. All the obtained results confirm the capability of the
design procedure to achieve a collapse mechanism of global type. The
importance of this theory and therefore of the design structures is the
possibilities to maximize the energy dissipation capacity and global
ductility because all the dissipative zones are involved in the
corresponding yielding pattern. Conversely, beam-column hierarchy
criterion, commonly suggested by seismic codes, appears only as a very
rough approximation when compared to the TPMC and its theoretical
background. During the study has been realized the implementation of a
graphical interface for the design of reinforced concrete frames. The
program works as a pre- and post- processor of a routine calculation for
the design of frames with kinematic theorem of plastic collapse. The aim
oJ this software is give the possibility to design according to TPMC
me tho do logy, through the use of a technological instrument, simple to use
from all types of users, even not IT experts. [edited by author] | it_IT |
